When ax3+bx-6 is divided by x+3,the remainder is 9. Find term of a only . The remainder when 2×3-bx2+2ax-4 when it is divided by x-2

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When ax3+bx-6 is divided by x+3,the remainder is 9. Find term of a only . The remainder when 2×3-bx2+2ax-4 when it is divided by x-2

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Diễm Thu 3 years 2021-08-26T11:45:58+00:00 1 Answers 11 views 0

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  1. niczorrrr
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    2021-08-26T11:47:56+00:00
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    Answer:

    a)  a   = – ( 5 + b ) / 9

    b) no remainder

    Step-by-step explanation:

    A) ( ax^3 + bx -6 ) / ( x + 3 )

    Remainder = 9

    determine the value of a

    we will use the result of  if ( x + a ) divides polynomial g(x) the remainder is g(a)

    therefore given that ( x + 3 ) divides f(x) = ax^3 + bx – 6

    =  f( -3 ) = 9

    = a(- 27 ) – 3b – 6 = 9

    = -27a  = 9 + 6 + 3b

    therefore the term ‘a’ = – ( 15 / 27   + 3b / 27 )

                                        = – ( 5/9 + b/9 )

                                     a   = – ( 5 + b ) / 9

    b) Find the remainder when (2x^3 – bx^2 + 2ax – 4 ) is divided by (x-2 )

    given that ( x -2 ) divides f(x) = 2x^3 – bx^2 + 2ax – 4

    also given a =  – ( 5 + b ) / 9  from previous polynomial above

    = f(2) = ?

    = 2(8) -4b + 4a – 4

    = 16 – 4b + 4 ( – ( 5 + b ) / 9 ) – 4

    = 16 – 4b + (( -20 – 4b ) / 9) – 4

    = 16 – 4b – ( 20 – 4b ) / 9)  – 4

    = 16 – ( 32b – 20 ) / 9)  – 4  = ?

    therefore the remainder ‘b’ =  ( -108 + 20 ) / 32  = – 2 3/4

    since the remainder is negative there is no remainder then

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Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )